1. Field of the Invention
The present invention relates to an airflow detection apparatus.
2. Description of Related Art
The airflow detection apparatus is essential in many applications. High power-density electronics are liable to overheat and self-destruct when cooling-fan failures go unnoticed. Therefore, it becomes necessary to use some reliable means for airflow detection.
Usually, either a mechanical pressure-actuated vane switch or one of the various types of heat-transfer-based airflow sensors is employed. The mechanical pressure-actuated vane switches are inexpensive, but have low sensitivity. The heat-transfer-based airflow sensors have high sensitivity, but are expensive.
What is needed, therefore, is an airflow detection apparatus which can solve the above the problems.